Pitster stroker 145 cc

just got her running ........using the stock bore this is a nice easy big cc mini motor we are prototyping for Pitster......with our g2 cam and a mild head this thing yanks away from a std. 125cc like it was standing still. Now we are @ 5 pm so i can dyno this beast GPX . dyno runs will be up tommorow.It sounds like our 160 cc KLX .....braaaap!!!!

Cant wait to see dyno! That sounds awesome!!!

You the man Dan, look forward to hearing the results. Call me 866-686-7869

we'll it's done....it gained 3hp and 3 ftlbs everywhere and it over revs better to 10800 than it ever did. i can't post the runs yet because my buner is down but maybe this weekend......std. hp was 8.0 @ 8000 rpm now we are 10.9 hp @ 8000rpm. and 11.9 @ 10500 rpm !!!

it used to take 7.5 seconds to pull from 20mph to 50mph now it does it in 5.9 seconds from 20 mph to 50 mph !!! very very strong smooth power. Feels great.

way to go dan !

great job

looks like we have a killer gpx engine on our hands now

Nice, what carb were you using?

Vince, I think I need to go full crazy mad scientist on one of dem... : )

soo what class r u planning on running this thing in if it a 145cc :banghead:

cr kid i'm shipping it monday to the BOSS. dyno sheets and all......someone is gonna be a lucky guy. it should run side by side to your average 117 se.....maybe a little more fun than that because of the insane low end it has......the 22 mm std. carb and a big gun pipe worked fine everywhere in the rpm band.....from low low end i mean diesel bottom to the highest revs peak @ 11000 it is clean as a whistle on the tune up.

I'm drooooooling!! I'll be sending you more cranks and engine's to get built real soon! :banghead::banghead:

Have you tested it with any other carbs yet, 24mm, 26mm? Or do you think the stock 22mm is ok?

Thanks Dan!

the 22mm that comes on this thing blows my mind how good it is.i'm sure there is more there with the 26mm but for now this thing is near perfect. Run it!! played with the fuel screw a little and raised the needle one clip......it might like a little more main jet also but i didn't have one, but hey for a lower end 22 mm it's impressive.

soo what class r u planning on running this thing in if it a 145cc :banghead:

u can probably run an open 12 class, slap some bigger wheels on and battle the klx's

WOW!!! This is definately going to be a big seller! Just let us dealers know when these will be available for sale to the public.

I have got to git me one of deez!!

Great job to everyone involved! The dedication to the product is the main reason these are doing so well. Keep it up! :banghead:

were not done yet !!

What Is The Standard Main And Pilot For A Gpx Pitster Motor?thanks

Can you get a big bore yet online and where can you get a head for the GPX motor?

The 145cc is going to retail for about $950 (for the work to be done to your engine) Pulls like a freight train! Anyone with a Pitster Pro engine (GPX) can get this kit done in about two weeks. Or you can buy an engine complete with ALL the work done for $1295. call for more details.

Thats a 145cc start in any gear four speed manuel with carb ready to race!


I promise I'll have dyno's ASAP.

We can get you a head if you need one.


man maybe i should have gotten a bad azz pit bike instead!!!....LOL

man maybe i should have gotten a bad azz pit bike instead!!!....LOL

you know thats right!


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